Charlize Theron: My Son Said 'Mama Pretty' on Oscar Night

Forget the fans, her fellow stars, and the fashion police, both official and otherwise. For Charlize Theron, it was the opinion of just one Oscar-watcher that mattered: Her 2-year-old son, Jackson.

While she got ready for the big night, "he was watching," Theron, 38, told PEOPLE at Fame & Philanthropy Post Oscar party.

"I got my first 'mama pretty' tonight, so it was a slam-dunk for me," said the actress. "I'm very happy right now," she said, adding that motherhood is "really good."

From the looks of it, her relationship with Sean Penn seems to fall in the same category.

Sean Penn and Charlize Theron

Jason Kempin / Getty

At the post-Oscar bash held by Fame & Philanthropy – whose mission is to harness the power of celebrity to raise awareness and support for charitable organizations – Theron and Penn, 53, held hands and sat very close in the VIP area.

Despite being swarmed by fans, the pair looked quite happy and comfortable together. Not that this appears to be anything new: on their recent Mexican getaway, the stars "were inseparable," an eyewitness told PEOPLE. "They looked completely enamored with each other."